Air-compressor.



No. 731,692. I

V PATENTED JUNE 23, 1903. G. DE LAVAL & G. P ABORN. l

AIR COMPRESSOR.

APPLICATION FILED JULY 25, 1901. K0 MODEL.

2 SHEETSSEBET l.

No. 731, 92. PATENTED JUNE 2a, 1903.

G. DE LAVAL & G. P.'ABORN.

AIR COMPRESSOR. APPLICATION mun JULY 25, 1901.

2 SHEETS-SHEET 2.

- no MODEL.

j iNVENTORS.

7715/); ATTORNEYJ UN TED STATES Patented June 23, 1903.

PATENT OFFICE;

GEORGE DE LAVAL, F CAMBRIDGE, ND GEORGE P. ABORN, 0E BOSTON, MASSACHUSETTS, ASSIGNORS To THE GEO. F. BLAKE MFG. 00., OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

AIR-COMPRESSOR.

SPECIFICATION forming part of Letters Patent No. 731,692, dated June 23, 1903.

Application filed July 25,1901. Serial No. 69,638. (No model.)

To all whom it may concern:

Be it known that we, GEORGE DE LAVAL, residing in Cambridge, Middlesex county,and GEORGE P. ABORN, residing in Boston, Suffolk county, Massachusetts, citizens of the United States, have invented certain new and useful Improvements in Air-Compressors, of which the following is a specification.

Our invention relates to air-compressors;

A and it has for its object to lessen the amount of air compressed and furnished to the receiver should the pressure in the receiver reach above normal. We may accomplish this by holding the inlet-valves of the com- 1 5 pressor beyond the usual time of their closing and onlypartially closing the inlet-valves.

We will describe an air-compressor embodying our invention and then point out the novel features thereof in the claims. I

In the accompanying drawings, Figure 1 is a view in side elevation of an air-compressor having our invention'applied thereto and an engine operating the compressor. Fig. 2 is a detail side elevational view of an air com- 2 5 pressor embodying our invention. Fig. 3 is an end elevation of Fig. 2. Fig. 4 is a detail sectional view of a portion of an air-compressor and showing an .inlet and outlet valve. 3:) ism applied to an inlet-valve. Fig. 6 is an elevation, on a'larger scale,-of a mechanism for'controlling the supply of steam to the englne. A

Similar letters of reference designate cor- 5 responding parts in all the figures.

A represents the cylinder of the compressor, and B a valve for controlling an inlet-opening through which air is drawn into the cylinder. An inlet-opening and valve are provided for 40 each end of the cylinder.

0 represents a valve controlling the outlet for compressed air to a receiver or reservoir. (Not shown.)

0 represents a conduit through which compressed air is conducted to the receiver from the compressor.

It will be understood that a valve or valves C are provided for each end of the cylinder..

Each inlet-valve B is provided with a stem or shaft b, on which is keyed a latch-disk b.

Fig. 5 :isa detail view of a mechair.

Each disk I) is provided, preferably on its periphery, with a shoulder, notch, or projection 19 with which a latch or finger b is adapted to engage. Each latch or finger b is carriedby a lever b which is loosely fulon each stem 17. Each lever-arm b is provided with a projection or extension I), which engages with a lug or other devicelf, provided on each disk I). The lever-arms b are rocked by meansof a three-arm lever E, constituting a wrist-plate, fulcrumed on a sliding block F, a rod or link 11 being provided between each lever-arm b and an arm of the lever E. The lever E is operated from the eccentric cl through, rod E, connected. to rockarm D, so that it moves, together with its connected lever b reversely to the levers b The operation of the mechanism so far as described is as follows, only one valve being considered, as the operation of both valves is the same, the only difference being that when one inlet-valve is being opened the other inlet-valve is being closed. The several parts will have to be so arranged relatively that this can be accomplished. As the eccentric d operates the pitinan D in one direction a lever 19 is moved on its fulcrum to bring the finger or latch 19 into position to engage the notch 19 on the disk, and in the pitmans movement in the reverse direction the lever and latch cause the disk to move, and thus open the valve. The disk I) when moved to open the valve brings the lug b into position 5 to be operated upon by the lever-arm b". The lever E is so timed to rock on its fulcrum that when the levers 19 move the disks to open the valves the lever-arms b are moving away from the position they occupy after lever.

they have moved the disks to close the inletvalves. Therefore when the levers b have opened the valves the eccentric, through the lever E, is ready to move the lever-arms b into engagement with the lugs b to move the disks and close the inlet-valves. When the lever-arms b move the disks to close the valves, a cam or other device b engages with a hook I), connected with the latch b causing the latch to hold them out of the way of the disks when the disks are being moved by the lever-arms 1) This is the operation of the compressor when the pressure in the receiver is normal. Should the pressure in the receiver go above normal, it is necessary in preventing waste of power, compressed air, &c., to stop the complete compression of all air in the cylinder or to slow down the engine to have a slower compression, and thus save steam and power. To prevent compression of all the air, it is only necessary to delay the closing of the inlet-valves or to prevent their entire closing. To do this in this instance, it is only necessary to shift or change the position of the fulcrum of the lever E so that the throw of its arms will not cause the lever-arms b to move the disks 1) at the usual time. This is done by lowering the fulcrum of the lever E, which causes the lever-arms b to move farther away from the point at which they will engage with the lugs b thereby actuating said disks I) later in the pistonstroke. Therefore with the lever-arms b out of their usual position when the levers I) move the disks to a position to have theinletvalves delayed in closing orto be only partially closed their latches b will merely ride on the peripheries of the disks b without in any way affecting the disks. The position of the fulcrum of the lever E is in this instance controlled by the pressure in the receiver. A pipe or conduit connects the receiver with a cylinder F, in which a piston f moves. The rod f of the piston is connected with the sliding block F, on which the lever E is fulcrumed. Guides f are provided for the block F. The piston is moved against the action of aspring ffiwhich is set to resist normal pressurein the receiver. Any pressure above normal will move the piston to lower the fulcrum of the The pressure of the spring is regulated by means of the screw-plug f through which the piston f moves. If desired, however, the positionof the fulcrum maybe controlled by water-pressure, in which case a mechanism such as is described in our copending application, Serial No. 69,639.

In addition to the above-described means for regulating the time of closing of the intake-valves the pressure in the receiver above normal may also be employed to cut off the amount of steam supplied to the engine G, which operates the compressor. The engine G is here shown as consisting of a Corliss steam-cylinder, the trips of which are shown in a conventional manner. These trips are regulated by means of a three-arm lever g,

fulcrumed on a stationary bracket g, and connections g (conventionally shown by dotted lines). The lever g is rocked by an arm 9 which arm is operated from a piston movable within a cylinder 9 Rods g g and a rocking lever g serve to connect the piston with the arm 9 The piston is provided with adjustable weights to withstand diiferent pres- Sures. The arm 9 is also connected by a link g with a lever 9 fulcrumed on the bracket g and carrying a weight g at one end and having a rod movable-in and out of a dash-pot at its other end. Intermediate of its ends it has a connection with the sliding collar g of the weights of governor, which are rotated in the ordinary manner of Corlissengine governors.

For the regulation of steam-supply to a plain slide-valve steam end the mechanism above described would operate a balanced throttle-valve.

It is obvious that the above devices or mechanisms are applicable to a single cylinder, two-stage compressing-cylinder, and three-stage compressing-cylinder or more.

What we claim as our invention, and desire to secure by Letters Patent, is

1. In an air-compressor, the combination of inlet-valves each having a stem, a disk fixed on each stem and having a plurality of notches or projections, levers upon said stems provided with means for temporarily engaging the notches or projections and operated from the eccentric of the engine to move each disk in one direction, and a device operated from said eccentric and controlled by the varying pressure of the air compressed, and connected for positively and variably moving the disks in an opposite direction, in accordance with the variations of air-pressure, to close said valves.

2. In an air-compressor the combination of inlet-valves, each having a stem, a disk fixed to each stem, a lever-arm adapted to engage and move each disk in one direction, which lever-arms are operated from the eccentric of the engine, a lever-arm adapted to engage and move each disk in the opposite direction, a fulcrumed device for operating said lastmentioned levers, and means for shifting the position of said fulcrumed device whereby its throw in closing the valves will be changed.

3. In an air-compressor, the combination with the inlet-valves, each of which has a stem, of a disk for each valve fixed on each stem, an arm operated from the eccentric of the compressors engine for engaging and moving each disk in one direction, a second arm for each disk, which when engaging and operated moves its disk in the opposite direction, a lever having a movable fulcrumed device for operating said last-mentioned arms, said lever being rocked on its fulcrum from said eccentric, and means operated by excess pressure from the air-receiver for shifting the position of the fulcrum of said lever bodily, whereby its throw is lessened.

4. In an air-compressor, the combination with the inlet-valves thereof,-each of which has a stem, a disk provided on each stem,

means operated from the eccentric for moving said disk to openthe inlet-valves, means comprising a lever having a shiftable fulcrum for moving the disk to close the inlet-valves,

and a device operated by excess pressure in the reservoir or receiverfor shifting the posiby its effective throw in closing the valves is varied.

5. In an air-compressor, having a cylinder,

piston and inlet and outlet valves, the comtion of the fulcrum of said lever bodily where- 

